Necessary Condition
by orianna-2000
Summary: Donna learns an essential truth about Time Lords: with regeneration comes the solace of a clouded memory.


_This is a non-profit work of fan-fiction based upon the television series_ Doctor Who_. All related characters, places, and events, belong to the BBC, and Russell T. Davies, used without permission. This story, with all original content, belongs to the author, © 2007. _

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_**Necessary Condition**_  
by Orianna2000 

"_Not the power to remember, but its very opposite, the power to forget, is a necessary condition to our existence." — _Sholem Asch

_-.-.-.-.-.-.-_

Donna screeched and slapped the face of the stranger standing before her. "Send 'im back! You send 'im back right now! You don't know who you're messing with, but if you know what's good for you, mister, you'll—"

"—Send him back. Right, got that, thanks." The ginger-haired bloke rolled his eyes and held one hand up to his stinging cheek. "Is it just me, or has the human race gotten more stupid since the last time I visited Earth?"

"Oi! Just you watch who you're insulting, mate." Donna glanced around the console room wildly. Her gaze fell upon the coat rack in one corner, and she began inching her way toward it, talking all the while. "This isn't just any old ship you happened to hijack, you know. This is the TARDIS. T-A-R-D-I-S, TARDIS. That stands for Time and . . . and . . . well, never mind what it stands for! It means this is no ordinary ship, is what it means. She's alive, she is. And she doesn't like hijackers. Neither does the Doctor, and believe me, when he gets back, you're going to wish you'd never set foot on his ship!"

"Believe me, I already do," he muttered.

"What was that?" Donna narrowed her eyes at him. The coat rack stood within arm's reach.

"Oh, nothing. Nothing at all. Look," he said, folding his arms, "there is one flaw in your argument, if you don't mind me pointing it out. You see, I insulted the human race. And your ever-so-clever comeback was to tell me all about this ship. Not yourself, mind, but the TARDIS, which, as it happens, I agree is a simply brilliant ship. Beautiful and clever and fantastic, all of which has no bearing whatsoever on _your_ intelligence."

"All right, that's enough!" She grabbed the coat rack and brandished it like a weapon. When she shook it menacingly, the Doctor's tan overcoat swayed back and forth from one of the hooks. "Now, you're going to tell me everything I want to know. No funny business, all right?"

"So says the woman threatening to smother me with a coat? A rather nice coat. Looks like one I used to have, matter of fact."

"Shut it. I don't want to hear about your old coat!"

"No, I shouldn't think so. Listen, do you mind if I just. . . ?" And he leaned forward, hands held up in the mostly-universal signal for surrender, and snagged the overcoat off the end of the coat rack. With a fluid movement, he tossed the coat over the branch of one of the support struts. "Sorry, I just didn't want such a nice coat to get ruined, should you decide to charge at me with that thing. Blood is terribly difficult to get out of wool, you know."

"Who _are_ you?" Donna asked with exasperation.

"Me? Oh, didn't I say? I'm the Doctor."

"The Doctor," she said in flat disbelief.

"That's right, I'm the Doctor. And you are. . . ?"

"None of your bloody business, that's who! Now stop fooling around and tell me who you really are. Better yet, tell me what you've done with the Doctor! The _real_ Doctor. I won't have you running about impersonating him."

He reached up and scratched the side of his nose. "Hmm. A bit bigger than I remembered."

Donna's eyes widened and then narrowed. Her cheeks flushed and she opened her mouth more than once in trying to think of a suitable comeback.

"Oh! No, not you! The nose, I mean. Sorry! The nose is a bit . . . Um, look, Donna, wasn't it?" He took a step towards her, only to stop when she shook the coat rack at him. "See here, Donna. I _am_ the Doctor. At least, I'm fairly certain that I am. I'd calculate the exact odds at being around ninety-nine and a half percent, give or take three-tenths of a percent." He tilted his head. "Hold on, is that right? Three-tenths? No, hold on, let me think. Nine . . . twenty seven . . . carry the four . . . twelve . . . multiply by seventeen . . . ah! Sorry, make that three-quarters of a percent."

Donna laughed short and hard. "Shows how much you know, Mister Alien. It's impossible, that's what. If you added three-quarters of a percent to ninety-nine and a half percent, you'd end up with more than one-hundred percent. I may only be a stupid human, but I did my O-level maths and I know that that's impossible."

"Ah. Well, not where I come from." He shrugged with a bit of an embarrassed smile.

"And where might that be? Raxicorico . . . Raxicorica . . . That place where the Slitheen come from? Have you got a zip in your forehead? Lemme see, lift up your fringe."

With a tolerant sigh, he did just that, revealing a smooth, pale forehead. "No zip. See? I'm as . . . well, no, I'm not as human as you are. But close enough, right?"

"You know what species the Doctor is? No one knows that." She lifted the coat rack a few inches and tried to look as though she knew how to use it. "Prove it."

"Well, I'm not from Mars, am I?" He sighed. "I'm a Time Lord. That prove anything?"

"Matter of fact, it doesn't. Plenty of people know he's a Time Lord. That isn't what I asked, now is it? I said what species is he? Time Lord's an occupation. Not exactly a job that anyone could apply for, but like a caste, of sorts. It's not his race."

"Well then, Donna. I guess it's a good thing I'm Gallifreyan, then isn't it?"

The coat rack shook a bit. "How can you know that? Nobody knows that! Look, I don't care. Honestly, I don't. Whatever it is you're up to, you can go on doing it. Just give me back the Doctor and we'll be on our way. All right?"

He looked up at the ceiling. "Another stupid human. Why do I keep going back there? Nothing but apes, the lot of them!"

"Oi! I've had enough of your insults, I have."

"Donna, look at me! It's me! Honestly, it's me!" He tried to smile, but stopped at the harsh glare Donna sent his way.

"I'm not stupid, you know. Like I said, you can go on doing whatever it is we interrupted. Just send back the Doctor and we'll leave you alone."

"Donna, I can't send him back. He's gone."

The coat rack fell to the ground with a loud clatter. "Oh, God. You've killed 'im! I knew it, you've killed 'im!"

"No. No, no, no. No! No. Listen, he isn't dead. Well, yes, he is. In a manner of speaking."

"Murderer! He's a good man and you've killed 'im! The only man who ever treated me with respect and decency and you've gone and murdered 'im! You—" And she lunged at the man with short ginger hair.

"No! No, listen, you've got it all wrong!" He slapped away her hands as she attacked him, but he didn't see the right hook coming.

A glass jaw—just like the Doctor, Donna noticed with satisfaction, as the man's eyes rolled up and he crumpled to the floor of the TARDIS.

"You're the one who's got it wrong, mate. You've made the biggest mistake anyone's ever made." Donna stood over the unconscious body. "We needed 'im, you bastard! We needed the Doctor! Now what the hell are we supposed to do? And . . . oh, God! How am I supposed to get home? I'm stranded here, on this God-forsaken moon or whatever the hell it is. What?"

She heard someone clearing their throat and saw a bit of light out of the corner of her eye. Indignant and more than a little unnerved, she spun around. "What's that? Who's there? No one can get into the TARDIS. That's what he tells me, but look at this place! Crawling with visitors. And who might you be? Friend of his?"

"My name's Rose. Rose Tyler."

Donna blinked. Surely not . . . _the_ Rose Tyler?

"But you're dead," she said stupidly. Only then did she realize that the young woman standing in front of the console wasn't real. Real people didn't look all faded and flickery, like the picture on a worn out telly. With a face that the Doctor might have rudely compared to a confused cow, Donna circled the image of Rose Tyler.

"If the TARDIS is playing this message," Rose said, "then it means that you could use some help right now. I know you think you've just seen the Doctor explode, and afterwards a stranger stood in his place. But don't worry—he does this all the time."

Donna crossed her arms. "Oh, he does, does he?"

"It's totally natural, nothing to worry about," Rose continued. "But do me a favour, yeah? When he wakes up, give 'im a slap for not telling you ahead of time. And if he complains, tell 'im that I said he deserved it."

"Right," Donna said. "Slap the Doctor. Got it. What for?"

"See, Time Lords have this little trick. They call it 'regeneration'," Rose said.

"Wait a minute, I've heard that word! Regeneration. The Doctor kept saying it, over and over, before he . . . before that other fellow showed up. He said it, but I didn't know what it meant. I figured he was raving! Not that he always makes sense, mind, but . . . Oh, sorry. Didn't mean to interrupt." She closed her mouth to let the hologram continue.

"Now, I know he hasn't told you anything about regeneration, stupid git, but it means that he was injured or sick—something fatal. But he's a Time Lord, and as I'm sure you've heard a hundred times by now, Time Lords are superior in _every_ way." Rose and Donna rolled their eyes in unison. "But for this, he's right. If he didn't regenerate, he really would die, and that'd be a lot worse."

Donna listened as Rose explained exactly how this regeneration worked and what it meant. She blinked back tears as Rose detailed her heartbreak over losing her first Doctor, because if she stopped to really think about it, she'd be bawling like a baby. She did feel better, though, once Rose explained how much she'd come to love the next Doctor.

"For all their differences, they're still the same man," she said. "And if you love the Doctor, you have to love all of him. Not just the one you started out with."

Long after the hologram faded, Donna gave a speculative glance to the man lying on the floor with a bruise on his left cheekbone. He stirred a bit and Donna stood over him with her arms crossed. "Well, don't think you're going to get away with this, mate. There's secrets as are good and necessary, and then there's just plain being stupid."

The Doctor blinked up at Donna. "I'm sorry, did you just call me _stupid_?"

"And you deserve it, too, you big lump. There's more that you deserve, but let's get you on your feet, first." She helped him up and then eyed him. "No regeneration sickness? No bits of Vortex leaking out all over the place? No brain implosions?"

"Ah . . . no. No, I don't think so." He looked at her with confusion, then winced as she slapped him for the second time in the past half hour. "Ow! What was _that _for?"

"That was for not telling me what regeneration is all about and that you were planning to do it."

"Well, I wouldn't exactly say _planned_, but . . . mfph!" He found his next words muffled as Donna's lips pressed to his. For several seconds he couldn't move, then he pulled back and stared at Donna, with even more fear in his eyes than when she'd slapped him. His jaw worked a few times, but no words would come. Finally, he fell backwards onto the jump seat. "Donna?"

"Yes, Doctor?"

"Much as I'd like to pretend that the past few minutes never happened, I simply have to ask—no. No, you know what? I don't want to know. I really _don't_ want to know. I just . . . no! Never mind. I'm not going to ask. I'm just going to pretend that the last few minutes didn't happen. I woke up from my regeneration and you said you were happy to see me, and we're off to our next adventure, yeah?"

She stared at him. "You really are him, aren't you? She was right."

He shook his head, bewildered. "May I remind you that I _have_ just regenerated, and therefore might not exactly be operating under peak mental efficiency? And yes, I will deny that I just said that, should this ever come up in the future."

"Oh, I don't know. I was told that just after your _last_ regeneration, you were able to fight off a Sycorax invasion,_ single-handedly_." She emphasized the last word and then winked to underscore the pun. "And in your jim-jams, no less. Bet that was a sight!"

"They weren't _my_ jim-jams," he protested. "They were . . . well, I don't recall whose they were, but they weren't mine. They fit so nicely that I kept them, though I don't suppose they'll still fit. New body, different size. Shame that—I really liked them. I suppose the bloke I stole them from liked them too. What _was_ his name?"

"Howard, from the market," Donna supplied helpfully. "And he kept fruit in his dressing gown. I know all about it. I also know that you brought down Harriet Jones' administration with six words. And I even know what they were. Fancy that!"

"Oh, come on. Six words?" He scrunched his forehead in thought. "You sure about that? Funny, I don't recall what they were."

"'Don't you think she looks tired?' That's what you said, innit?"

The new Doctor's mouth gaped, just a little. "I do believe you're right. But. . . . How did you . . . how could you possibly. . . ?"

"Oh, I had a nice long chat with an old friend of yours."

"Did you? And who might that be?" At Donna's secret smile, the Doctor looked thoughtful. "You know what, never mind what I said a minute ago. Why_ did_ you kiss me? More importantly, why did you slap me and _then_ kiss me? The two generally don't go together, at least, not in my experience. Well, not unless the kiss comes first and is unwanted or out of line . . . then a slap, under those circumstances, would be perfectly understandable. But a slap and _then_ a kiss? Unheard of."

"Doctor?"

"Yes, Donna?"

"Some things never change. What with all I put up with—ought to be getting hazard pay, I should." She reached over and touched his strawberry blonde sideburns. "Going to take some getting used to, this new face of yours. Bit different."

"Good different?"

She shrugged. "Just different. But that's what she said, isn't it? That it'll take time to get used to everything. New face, new voice, new mannerisms, new everything. Nothing wrong with it, it's just different."

"Who?" He looked at her. "Who said that?"

Instead of answering, Donna ran her hand down the front of the old pinstriped suit. "Going to need some new clothes, you are. You're a bit taller, I think. Not as skinny. Going to split the seams of that old suit if you take a deep breath. Does this mean a shopping trip?"

"I usually find something in the wardrobe. And you didn't answer my question."

"Usually? Hold on! What d'you mean, _usually_? How many times you done this?"

"Oh," he said, chewing on his bottom lip. "Quite a few, actually. Has it been a dozen, yet? No, not quite. This is my eleventh self, so my tenth regeneration."

That time, he expected the slap, but it still stung.

"I really wish you'd stop doing that," he said.

"And don't expect me to kiss it better, this time! I only did it the once, because she asked me to. Don't start thinking I've gone soft on you or anything."

The Doctor reached up and grabbed Donna's wrist. "Who? Who were you talking to?"

"Rose," she said quietly. "I was talking to Rose. She wasn't here," she added quickly, "it was a hologram, a recording. She said she left it with instructions to be played in case you ever regenerated again. Said it would be a nasty shock to someone not expecting it, and that it wasn't fair of you to keep your companions in the dark about it. And she's right. Would've been nice to know that you hadn't actually exploded or been kidnapped or whatever."

"Rose. . . ?"

"That's right. Rose! The one you're always talking about. The slap was her idea. So was the kiss, so don't be getting any filthy ideas."

"A companion of mine?"

"Don't be stupid! No, I mean the Dalek named Rose. They got tired of not having individual identities, and so the one I met is calling itself Rose and goes about wearing feather boas and diamond earrings and goes to clubs every weekend. Of _course_ I'm talking about your companion!" She rolled her eyes. "The one you lost just before we met, remember? The one who broke your heart—excuse me, Mister Martian, your _two_ hearts. The one you never shut up about."

The Doctor shook his head , but then raised his eyebrows in memory. "Oh, yes. Rose! Blimey, that was a long time ago. Blonde girl, worked in a shop, didn't she? Rather brilliant, as I recall. I've the vague impression that I lost her, but I don't remember much about it, really. Regeneration dulls the memory a bit, you know. And, well, I'm always losing companions."

Donna stared for a moment, before nodding slowly. "She was important to you, yes. You lost her, a long time ago."

"That's too bad. Of course, it was bound to happen sooner or later. Companions never stay very long. They find something more important, or move on with their lives. Nothing personal, you know. Life goes on. I can't even recall how many have come and gone over the years. Quite a few, I expect." He paused, then looked up at Donna. "Why would she ask you to kiss me?"

Donna blinked through suddenly wet eyes. "Just a practical joke, I expect."

"Oh. All right, then." He jumped to his feet and started pacing around the console. His eyes lit up and he started playing with knobs and levers. "Well, then, Donna. It's a whole new universe out there! Shall we start exploring it?"

She managed to smile and nod, then took the Doctor's place on the jump seat. As the Doctor moved about with manic energy, Donna said quietly, "She would've been happy that you're finally ginger."

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_**Author's Notes:** This story was inspired by the now-confirmed rumors going around regarding series 4, specifically a photograph of Rose with Donna. Some fans wondered why Donna would be alone with Rose, and plot-bunnies started hopping around!_

_This time around, my beta-readers were **Humansrsuperior** and **Little Zink**, and **Alliegoestonz** provided the Brit-picking. _


End file.
